PFR5-1921BLK – Rear Subframe Rear Bush Insert

The Powerflex PFR5-1921BLK Rear Subframe Rear Bush Insert is a Black Series performance insert designed to stiffen the rear subframe mounting point on BMW F2X/F3X models, including the M135i, M140i, M235i and M240i. This insert fills the voids in the OEM subframe bush to significantly reduce flex, improve rear-end stability and sharpen overall chassis response.

SKU: PFR5-1921BLK
Position: Rear Subframe – Rear Bush Insert

Key Features

Black Series Polyurethane

– Maximum stiffness for track, drift and high-power setups
– Motorsport-grade compound
– Designed to eliminate unwanted subframe movement

Improved Chassis Control

– Reduces rear-end float and flex
– Improves stability during hard cornering
– Enhances rear traction and weight transfer control

Sharper Driving Dynamics

– Tighter, more predictable rear axle behaviour
– Better control during launches, direction changes and fast-road driving
– Ideal upgrade for tuned F2X/F3X M-Lites

Easy Installation

– Inserts into the OEM subframe bush (no pressing required)
– Quick, cost-effective handling upgrade
– Noticeable improvement with minimal NVH increase

Benefits

The PFR5-1921BLK insert transforms the handling feel of the F2X/F3X platform by removing the slack in the rear subframe mounts. The car feels tighter, more planted and more responsive — especially under hard acceleration and cornering. A must-have for fast-road and track-driven M135i/M140i/M235i/M240i builds.

Fitment

Suitable for:
– BMW M135i (F20/F21)
– BMW M140i (F20/F21)
– BMW M235i (F22/F23)
– BMW M240i (F22/F23)
– Also compatible with many non-M-Lite RWD F2X/F3X models

SKU: PFR5-1921BLK
Position: Rear Subframe – Rear Bush Insert

Installation Notes

– Fits into the factory rear subframe bush
– No press required
– Professional installation recommended
– Slight NVH increase is normal for Black Series components

About Powerflex

Powerflex Black Series bushes are engineered for motorsport applications, offering maximum stiffness, precision and durability. Ideal for drivers pushing their BMW M-Lite beyond OEM limits on track or fast road.